In general, in dialysis treatment, a blood circuit composed of a flexible tube is used to extracorporeally circulate the blood of a patient. The blood circuit mainly includes an arterial blood circuit having a leading end attached to an arterial puncture needle for collecting the blood of a patient, and a venous blood circuit having a leading end attached to a venous puncture needle for returning the blood to the patient. A dialyzer is disposed between the arterial blood circuit and the venous blood circuit, and the blood which is extracorporeally circulated is purified.
Part of the arterial blood circuit is connected to a flexible tube to be peristaltic which has more flexibility and a larger diameter than the rest, and the part is configured to be attached to a peristaltic pump disposed in the dialysis device. Normally, the peristaltic blood pump mainly includes a stator having an attachment recessed portion in which a flexible tube to be peristaltic is attachable; a retaining means that can firmly retain the flexible tube to be peristaltic attached to the attachment recessed portion; a rotor that is rotatably driven in the attachment recessed portion; and a roller that is formed in the rotor and that imparts peristaltic motion to the flexible tube to be peristaltic while compressing the flexible tube to be peristaltic.
In order to attach a flexible tube to be peristaltic to a peristaltic blood pump, a worker such as a medical professional needs to take and rotate the flexible tube to be peristaltic along the inner circumferential wall surface of the attachment recessed portion while manually rotating the rotor little by little. In other words, only a small clearance is provided between the inner circumferential wall surface of the attachment recessed portion and the roller due to the necessity of compressing and imparting peristaltic motion to the flexible tube at the time of rotational drive of the rotor, and thus in order to insert the flexible tube in the clearance, the rotor is manually rotated little by little and the flexible tube is attached to the entire attachment recessed portion. It is to be noted that attachment of such a flexible tube to be peristaltic is substantially common among not only a blood pump but all pumps called a peristaltic pump.
In the above-described peristaltic pump, work of attaching the flexible tube to be peristaltic to the attachment recessed portion of the stator is troublesome. For this reason, the applicant has proposed a peristaltic pump that allows a flexible tube to be peristaltic to be attached more easily and smoothly (see, for instance, PTL 1). The peristaltic pump is configured to regulate the movement of the flexible tube to be peristaltic in a longitudinal direction by fixing the upstream-side of the flexible tube, to be attached to the attachment recessed portion, and to allow the movement of the flexible tube to be peristaltic in a longitudinal direction in the downstream-side by the rotational driving force of the rotor, and it was expected that workability of attachment of the flexible tube to be peristaltic in the attachment recessed portion can be improved.